That's an excellent idea, my husband is going to give it a try tomorrow, perhaps feeding the tube into a hidden cage or something, it has already come quite close with food so food in the tube might just work.
The story is that there is a Chipmunk running round outside and in, when he gets a chance at my husbands work, they have been trying to catch as worryingly there may be rat poison around, fingers crossed your idea works.
I have found when catching rodents that encouraging it into a tube is the best way of catching. The tube must be open at both ends as an animal won't go in to what it perceives to be a dead end. In the past I have also scooped up a piggy that got lost under a bush by placing a large fishing net flat on the ground. When the piggy was in the centre of the net I scooped it up suddenly.